Measure from your C7 vertebrae (the one that sticks out from your neck) down your back in a straight line to the same level as the top of your hip bones. If you're between sizes, it is better to go with the smaller of the two sizes.

Frequently purchased together

Description

For a more comfortable hiking experience.

Experience new comforts while hiking with Black Diamond's Nitro 22 Backpack. With a 22-liter capacity, this backpack has plenty of space for all the food and layers you need for long-distant day hikes. ts ReActiv suspension system includes shoulder straps and a waist belt that move with you while hiking. This innovative system provides maximum efficiency, ensures a natural stride, balances load transfer, reduces knee stress, and eliminates sore spots and bruising.

Made with Black Diamond's OpenAir technology, the Nitro's back panel, waist belt, and
shoulder straps circulate airflow to keep you cool in warmer weather. The zippered panel access opens wide for easy gear retrieval. Black Diamond also equipped the Nitro with an external access hydration sleeve for your own reservoir, attachment loops for trekking poles or ice axes, and multiple pockets at the front, sides, and waist belt for electronics, valuables, layers, and snacks for the trail.